carpen
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Methylamine problem
Hi.
I'm a bit concerned due to a synthesis, that requires "Methylamine GAS". I know how to synthesize Methylamine.HCl, but how do one make Methylamine
gas?
Best regards, carpen
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turd
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The principle is simple: you react MeNH2.HCl with a base, use a drying agent to expel the MeNH2 gas from the resulting aqueous solution, dry the gas
and lead it into your stirred reaction/solvent taking care of suckback.
But since you have to ask such questions, you are not able to handle MeNH2 and there is no point in looking up the details. Besides, you are too
inconsiderate to follow forum guidelines and too lazy to search the literature, so why should anybody bother to help you?
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woelen
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Mix solid methylamine.HCl with solid NaOH and add a few drops of water. A fairly vigorous reaction starts and gaseous CH3NH2 escapes from the mix. At
the end of the reaction you need some heating. Be careful with this reaction, quite a lot of heat is produced and if it is done with too large
quantities of reagents, then you get a lot of gas at once, running the risk of overpressure in your apparatus.
Lead the gas through a column with dry NaOH to absorb any water vapor which goes with the gas as well. Do not use CaCl2 as drying agent, because that
absorbs CH3NH2 as well.
The chemical reaction itself is straightforward and very easy. The generation of a nice constant stream of CH3NH2 is not easy at all though, this
requires some intelligent thought and engineering of your setup.
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Nicodem
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Thread Moved
8-1-2014 at 06:26 |
carpen
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Thank you so much for your answer. Another question: If i use 10kg of solid Methylamine.hcl, how much solid NaOH, and water, should i use?
Appreciate it, thanks!
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DraconicAcid
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10 kg of methylamine hydrochloride is 148 moles of CH3NH3Cl, and will require 148 moles (5.9 kg) of sodium hydroxide. Please
note that this will produce 148 moles of methylamine, which will occupy over three thousand litres at STP. You would have to be very, very careful to
avoid overpressuring your system.
Why on earth would you want to deal with such large quantities when you have no idea what you're doing?
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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carpen
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Quote: Originally posted by DraconicAcid  | 10 kg of methylamine hydrochloride is 148 moles of CH3NH3Cl, and will require 148 moles (5.9 kg) of sodium hydroxide. Please
note that this will produce 148 moles of methylamine, which will occupy over three thousand litres at STP. You would have to be very, very careful to
avoid overpressuring your system.
Why on earth would you want to deal with such large quantities when you have no idea what you're doing? |
Thank you! My question was only hypothetical, and i'm curious. Of course, I won't use 10kg of MA at the same time.
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woelen
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The use of 10 kg is insane. You definitely need some control mechanism in order to obtain a constant stream of methyl amine. If you simply mix the
chemicals in larger than gram quantities and then add a little water, then you at once produce a LOT of gas and whatever reaction you do with the gas,
it will not be capable of absorbing all that gas at once and you certainly will have overpressure in your system with the risk of blowing up the
system.
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carpen
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The synthesis of a substance that i want to make I will have to dissolve 1,25kg MeNH2 gas in 12,5l MeOH (-20 degrees). So I guess I'll first have to
react MA.hcl with natrium hydroxide in a pressure reaction vessel and lead the evolving gas through a condenser filled with a drying agent and bubble
the gas into the methanol.
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DraconicAcid
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If I were to attempt a reaction such as this, I would dissolve/suspend the methylammonium chloride in a minimum of water (enough to make a slurry that
could be stirred), and then slowly add a sodium hydroxide solution with an addition funnel. The solubility of the methylamine would prevent sudden
pressure changes.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Magpie
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If you could clarify the process conditions it would help us to assist you.
Surely you don't have to dissolve all of the 10 kg methylamine in the 5L of methanol all at once do you? Or are you going to meter in the methylamine
gas into a reaction vessel containing the methanol over a certain period of time as it reacts with your substrate? If so, might we know the
substrate?
[Edited on 8-1-2014 by Magpie]
The single most important condition for a successful synthesis is good mixing - Nicodem
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ScienceSquirrel
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If I had little experience I would start with 50g not 1.25kg of methylamine hydrochloride
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Pyro
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those amounts sound like cookery to me...
I would make a suspension of methylamine HCl in MeOH, then add NaOH dissolved in MeOH to it with stirring.
remember: methylamine smells like shit, well, fish actually. but you get what I mean so wear old clothes and gloves
[Edited on 8-1-2014 by Pyro]
all above information is intellectual property of Pyro.  |
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plante1999
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Who would make kgs of methylamine without much if any chemistry knowledge.... I can't see basic household use for that...
Anyway, it may be possible to make it in-situe in the methanol using sodium hydroxide solution in methanol over methylamine hydrochloride.
I never asked for this.
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turd
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You are lying. You want to make us believe that you're planning to make a mole of MDMA according to https://www.erowid.org/archive/rhodium/chemistry/redamin.nab... but that at the same time you didn't find this document: https://www.erowid.org/archive/rhodium/chemistry/10pc-menh2.....
You neither have P2P nor MDP2P, you are just a transparent poseur. Yawn.
[Edited on 8-1-2014 by turd]
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Pyro
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who's to say he doesn't?
but hey, anything that contributes the the collection of information here is good.
all above information is intellectual property of Pyro. |
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carpen
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--
[Edited on 8-1-2014 by carpen]
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turd
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| Quote: | | I wont do any kind of bloody cooking |
Well, that's too bad, because as you might have noted this forum is
dedicated to amateur experimentalism. It's not supposed to be a freaky role-playing game where one pretends to be a drug tycoon. 
Anyway, the answer to your question is given in the link above.
[Edited on 8-1-2014 by turd]
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ScienceSquirrel
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Heading for Detritus.
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Turner
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| Quote: Originally posted by turd | | Quote: | | I wont do any kind of bloody cooking |
Well, that's too bad, because as you might have noted this forum is
dedicated to amateur experimentalism. It's not supposed to be a freaky role-playing game where one pretends to be a drug tycoon.
Anyway, the answer to your question is given in the link above.
[Edited on 8-1-2014 by turd] |
I honestly can't take anything you post seriously with a username like that
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bfesser
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Thread Closed
8-1-2014 at 16:53 |
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